Merge pull request #367 from 91khr/master

Add support for strike through which is supported by GFM

diff --combined syntax/markdown.vim
index e9df1ca049d81717b20c5096126dcb8669f76a81,aad7dc477eadcd81f7095d7cd7dbf6296f2323a9..86b10b0b9bd65b6d0a20fec4668169fd4d29b6d8
--- 1/syntax/markdown.vim
--- 2/syntax/markdown.vim
+++ b/syntax/markdown.vim
@@@ -36,14 -36,10 +36,14 @@@ syn sync linebreaks=
  
  let s:conceal = ''
  let s:concealends = ''
 +let s:concealcode = ''
  if has('conceal') && get(g:, 'vim_markdown_conceal', 1)
    let s:conceal = ' conceal'
    let s:concealends = ' concealends'
  endif
 +if has('conceal') && get(g:, 'vim_markdown_conceal_code_blocks', 1)
 +  let s:concealcode = ' concealends'
 +endif
  
  " additions to HTML groups
  if get(g:, 'vim_markdown_emphasis_multiline', 1)
@@@ -86,25 -82,25 +86,25 @@@ syn region mkdLinkTitle matchgroup=mkdD
  syn region mkdLinkTitle matchgroup=mkdDelimiter start=+(+     end=+)+  contained
  
  "HTML headings
 -syn region htmlH1       start="^\s*#"                   end="$" contains=mkdLink,mkdInlineURL,@Spell
 -syn region htmlH2       start="^\s*##"                  end="$" contains=mkdLink,mkdInlineURL,@Spell
 -syn region htmlH3       start="^\s*###"                 end="$" contains=mkdLink,mkdInlineURL,@Spell
 -syn region htmlH4       start="^\s*####"                end="$" contains=mkdLink,mkdInlineURL,@Spell
 -syn region htmlH5       start="^\s*#####"               end="$" contains=mkdLink,mkdInlineURL,@Spell
 -syn region htmlH6       start="^\s*######"              end="$" contains=mkdLink,mkdInlineURL,@Spell
 +syn region htmlH1       matchgroup=mkdHeading     start="^\s*#"                   end="$" contains=mkdLink,mkdInlineURL,@Spell
 +syn region htmlH2       matchgroup=mkdHeading     start="^\s*##"                  end="$" contains=mkdLink,mkdInlineURL,@Spell
 +syn region htmlH3       matchgroup=mkdHeading     start="^\s*###"                 end="$" contains=mkdLink,mkdInlineURL,@Spell
 +syn region htmlH4       matchgroup=mkdHeading     start="^\s*####"                end="$" contains=mkdLink,mkdInlineURL,@Spell
 +syn region htmlH5       matchgroup=mkdHeading     start="^\s*#####"               end="$" contains=mkdLink,mkdInlineURL,@Spell
 +syn region htmlH6       matchgroup=mkdHeading     start="^\s*######"              end="$" contains=mkdLink,mkdInlineURL,@Spell
  syn match  htmlH1       /^.\+\n=\+$/ contains=mkdLink,mkdInlineURL,@Spell
  syn match  htmlH2       /^.\+\n-\+$/ contains=mkdLink,mkdInlineURL,@Spell
  
  "define Markdown groups
  syn match  mkdLineBreak    /  \+$/
  syn region mkdBlockquote   start=/^\s*>/                   end=/$/ contains=mkdLink,mkdInlineURL,mkdLineBreak,@Spell
 -syn region mkdCode         start=/\(\([^\\]\|^\)\\\)\@<!`/ end=/\(\([^\\]\|^\)\\\)\@<!`/
 -syn region mkdCode         start=/\s*``[^`]*/              end=/[^`]*``\s*/
 -syn region mkdCode         start=/^\s*\z(`\{3,}\)[^`]*$/   end=/^\s*\z1`*\s*$/
 -syn region mkdCode         start=/\s*\~\~[^\~]*/           end=/[^\~]*\~\~\s*/
 -syn region mkdCode         start=/^\s*\z(\~\{3,}\)\s*[0-9A-Za-z_+-]*\s*$/         end=/^\s*\z1\~*\s*$/
 -syn region mkdCode         start="<pre[^>]*\\\@<!>"        end="</pre>"
 -syn region mkdCode         start="<code[^>]*\\\@<!>"       end="</code>"
 +execute 'syn region mkdCode matchgroup=mkdCodeDelimiter start=/\(\([^\\]\|^\)\\\)\@<!`/                     end=/\(\([^\\]\|^\)\\\)\@<!`/'  . s:concealcode
 +execute 'syn region mkdCode matchgroup=mkdCodeDelimiter start=/\(\([^\\]\|^\)\\\)\@<!``/ skip=/[^`]`[^`]/   end=/\(\([^\\]\|^\)\\\)\@<!``/' . s:concealcode
 +execute 'syn region mkdCode matchgroup=mkdCodeDelimiter start=/^\s*\z(`\{3,}\)[^`]*$/                       end=/^\s*\z1`*\s*$/'            . s:concealcode
 +execute 'syn region mkdCode matchgroup=mkdCodeDelimiter start=/\(\([^\\]\|^\)\\\)\@<!\~\~/  end=/\(\([^\\]\|^\)\\\)\@<!\~\~/'               . s:concealcode
 +execute 'syn region mkdCode matchgroup=mkdCodeDelimiter start=/^\s*\z(\~\{3,}\)\s*[0-9A-Za-z_+-]*\s*$/      end=/^\s*\z1\~*\s*$/'           . s:concealcode
 +execute 'syn region mkdCode matchgroup=mkdCodeDelimiter start="<pre[^>]*\\\@<!>"                            end="</pre>"'                   . s:concealcode
 +execute 'syn region mkdCode matchgroup=mkdCodeDelimiter start="<code[^>]*\\\@<!>"                           end="</code>"'                  . s:concealcode
  syn region mkdFootnote     start="\[^"                     end="\]"
  syn match  mkdCode         /^\s*\n\(\(\s\{8,}[^ ]\|\t\t\+[^\t]\).*\n\)\+/
  syn match  mkdCode         /\%^\(\(\s\{4,}[^ ]\|\t\+[^\t]\).*\n\)\+/
@@@ -119,7 -115,7 +119,7 @@@ syn match  mkdRule         /^\s*_\s\{0,
  " YAML frontmatter
  if get(g:, 'vim_markdown_frontmatter', 0)
    syn include @yamlTop syntax/yaml.vim
 -  syn region Comment matchgroup=mkdDelimiter start="\%^---$" end="^---$" contains=@yamlTop keepend
 +  syn region Comment matchgroup=mkdDelimiter start="\%^---$" end="^\(---\|\.\.\.\)$" contains=@yamlTop keepend
    unlet! b:current_syntax
  endif
  
@@@ -149,12 -145,17 +149,18 @@@ if get(g:, 'vim_markdown_math', 0
    syn region mkdMath start="\\\@<!\$\$" end="\$\$" skip="\\\$" contains=@tex keepend
  endif
  
+ " Strike through
+ if get(g:, 'vim_markdown_strikethrough', 0)
+     syn region mkdStrike matchgroup=mkdStrike start="\%(\~\~\)"    end="\%(\~\~\)"
+     HtmlHiLink mkdStrike        htmlStrike
+ endif
+ 
  syn cluster mkdNonListItem contains=@htmlTop,htmlItalic,htmlBold,htmlBoldItalic,mkdFootnotes,mkdInlineURL,mkdLink,mkdLinkDef,mkdLineBreak,mkdBlockquote,mkdCode,mkdRule,htmlH1,htmlH2,htmlH3,htmlH4,htmlH5,htmlH6,mkdMath
  
  "highlighting for Markdown groups
  HtmlHiLink mkdString        String
  HtmlHiLink mkdCode          String
 +HtmlHiLink mkdCodeDelimiter String
  HtmlHiLink mkdCodeStart     String
  HtmlHiLink mkdCodeEnd       String
  HtmlHiLink mkdFootnote      Comment